Two-diameter tool carrier



Sept. 29, 1964 L. G. OTTEMAN ETAL 3,150,717

TWO-DIAMETER TOOL CARRIER Filed June 15, 1961 2 Sheets-Sheet 1 INVENTORS:

L. G. OTTEMAN N. B. NEWMAN BY: ,1 ClJig? HEIR AGENT Filed June 15, 1961 G OTTEMAN ET AL TWO-DIAMETER TOOL CARRIER FIG. 2

2 Sheets-Sheet 2 so I 4/56 3 3 I L l 4 53 -57 54 Val FIG.2A

1 INVENTORS:

L.G. OTTEMAN N.B. NEWMAN ,Hrw

THEIR AGENT ,2

United States Patent 3,150,717 TWO-DIAMETER TOOL CARRIER Lloyd G. Otternan and Nicholas B. Newman, both of Houston, Tenn, assignors to Shell (Ii! Company, New York, N.Y., a corporation of Delaware Filed June 15, 1961, Ser. No. 117,210 Claims. (Cl. loo-66.5)

This invention relates to a well device adapted to be pumped through a string of tubing positioned Within a Well and pertains more particularly to a device adapted to be pumped through a well tubing together with a well tool connected thereto whereby the tool may be seated at a predetermined position within the well. In addition to positioning tools at a predetermined position within a well tubing, it is often desirable to position other well devices, instruments or equipment, for example gas lift valves, or to carry out certain operations such as opening or closing a plug in the tubing.

A recent development in the oil industry is the drilling and completion of wells at an offshore location where the wellhead assembly and production control units are positioned beneath the surface of a body of water and preferably close to the bottom of the body of water. With wellhead assemblies positioned on an ocean floor, a hazard to the navigation of boats in offshore waters is removed. Additionally, considerable savings are realized in that it is not necessary to erect a protective stationary platform around the wellhead in the manner in which they are presently employed to protect well casing and wellhead assemblies extending above the surface of the water. It has also been found necessary to position a wellhead on the ocean floor in water depth where it is not feasible to erect a stationary platform around a wellhead assembly.

However, the placement of wellhead assemblies on the ocean floor raises a new set of problems with regard to carrying out workover operations, maintenance or other operations in a completed well. Major workover operations call for the use of a barge positioned on the surface of the water above the well together with equipment for going down and entering the wellhead assembly and the tubing or casing strings connected thereto, and in some circumstances may result in the entire removal of the wellhead assembly to the surface during workover operations. In order to carry out some of the more simple workover or maintenance operations, such as the perforation of Well casing, the opening of a packer, the removal or insertion of a valve, the cleaning of paraffin from the tubing string, the opening or closing of a sleeve on valve, etc., it has been necessary to develop an entirely new line of well tools which can be pumped through a fiowiine from some remote location, oftentimes a mile or more from the well, and enter the well, passing down the tubing therein to be subsequently positioned therein for carrying out some preselected operation. After completing the operation, the tool in the tubing string within the well is subsequently removed, generally by reverse circulation.

While the problem of pumping a tool to the bottom of the well tubing string in order to carry out certain operations is fairly readily solved wherein the well tubing and the flowline on the ocean floor connected thereto are of constant diameter throughout their length, a problem rises when the tubing string within the well and the flowline connected thereto and extending along the ocean floor are of different diameters. Thus, in certain Wells, for example in high pressure wells, it may be desirable to use a 1% inch tubing string in the well. However, considerable back pressure would be encountered in the well in the event that the fiowline extending from the wellhead on the ocean floor to a production facility or to shore was of the same small diameter. Also, a small diameter flowline would be subject to plugging. In low pressure wells the casing size limits the tubing to 2 inches or 2%. inches. Back pressure on the formation is a big factor, therefore larger size fiowlines, say 3 inch to 4 inch ilowlines may be used. Thus, in order to reduce the back pressure on the well, it is preferred that the internal diameter of the fiowline be increased to 2 inches or more at the wellhead. It is readily apparent that a pumpable tool having a diameter of 1% inches cannot be pumped through a 2 inch flowline as the driving fluid would pass around it.

It is therefore the primary object of the present invention to provide an apparatus whereby a small-diameter well tool may be pumped through a fiowline of considerable length which is of a substantially larger diameter.

Another object of the present invention is to provide a pumpable well tool of large diameter having a pumpable pilot tool of smaller diameter attached thereto and disconnectable therefrom automatically when a junction between a small diameter and large diameter pipe is encountered.

A further object of the present invention is to provide a pumpable well tool having a pumpable pilot tool normally attached thereto, which tools will readily separate at change of pipe diameter with the pilot tool of smaller diameter continuing along the smaller diameter pipe while the large diameter pumpable tool remains latched to the inside of the large diameter pipe and remains in place until the small diameter pumpable pilot tool has returned and seated itself in the large diameter pumpable tool.

Another object of the present invention is to provide a pumpable well tool having a bore therethrough to permit the flow of fluid therethrough to transport a small diameter pilot pumpable tool down a small diameter tubing string.

These and other objects of this invention will be understood from the following description taken with reference to the drawing, wherein:

FIGURE 1 is a schematic view illustrating a wellhead assembly positioned on the ocean floor;

FIGURES 2 and 2A are diagrammatic views taken in partial longitudinal cross-section of the tool of the present invention, with FIGURE 2A forming an extension of FIGURE 2;

FIGURE 3 is a cross-sectional view taken along the line 33 of FIGURE 2A when the probe of the pilot pumpable tool is still in place;

FIGURE 4 is a cross-sectional view taken along the line 3-3 of FIGURE ZA showing the position of the latching dogs when the pilot tool has been removed; and

FIGURE 5 is a cross-sectional view taken along the line 33 of FIGURE 2A after the pumpable tool and its pilot connected thereto have started to move upwardly out of the seated position of FIGURE 2A.

Referring to FIGURE 1 of the drawing, a wellhead assembly is shown in its position below the surface 11 of a body of water and preferably on the ocean floor 12. The wellhead apparatus comprises a platform 13 secured near the top of a conductor pipe or surface casing 14 which in turn extends into the earth below the body of water and is preferably cemented therein in a conventional manner. The wellhead assembly may also be provided with two or more vertically positioned guide columns 15 and 16 which are fixedly secured at their lower ends to the platform 13. A well casinghead 17 is mounted on the top of the conductor pipe 14 with a control equipment housing 13 closing the top of the casinghead and/ or any casing or tubing suspension equipment employed on the wellhead assembly, as Well as containing the various control valves and other control equipment normally used on the top of a well of this type.

Emerging from the housing 18 are a pair of flowlines 20 and 21 which preferably bend in long sweeping curves from a vertical position down to a substantially horizontal position so that they can run along the ocean floor 12 to a remote location where fluid from the well, and normally from other wells, is collected, metered and treated. Such a collection station may be several miles away. During the production of the well, normally only one of flowlines 253 or 21 is employed in transporting fluid away from the well. The well may be provided with one or more strings of well casing 22 suspended within the well, along with two tubing strings 23 and 24. However, in other well installations wherein a single tubing is utilized, the second flowline may be in communication with the annular space between the tubing string and the adjacent well casing. The flowlines 2t; and 21 may be of small diameter coming out of the well and increase, as at 25 and 26, respectively, to larger diameters. In practice, it is actually only necessary to have one of the flowlines, say flowline 21, have an increased diameter if flowline 21 is the one by which production fluid is to be transported from the well.

Referring to FIGURES 2 and 2A, it may be seen that a seating shoulder is formed within the portion 26 of the flowline 21 where it increases in diameter. A cooperating seating shoulder or surface 31 is formed on a pumpable tool carrier intermediate at the ends thereof.

A preferred design of the two-diameter tool carrier of the present invention comprises a central mandrel 32 and 32a connected together by a flexible joint 33. Mounted on the central mandrel 3232a are one or more sealing elements or packers 34 and 35 of any suitable design which are held thereon by suitable sealing-element or packer-retaining cups or rings 36 and 37, 38 and 39, respectively. Preferably, the body member 32-32:: is provided with a flexible linkage 33, such as a ball-in-sockct joint, as a point between the sealing elements 34 and 35 so as to facilitate movement of the tool carrier in curved sections of a well tubing or flowline.

Since the possibility always exists that any tool attached to the tool carrier may become stuck in a well, the tool carrier is preferably provided with a fishing head 43 whereby a retrieving tool (not shown) may be run through the tubing string to latch onto the fishing head 43, thereby permitting removal of the tool carrier and any tool connected thereto. The retrieving tool may take the form of another similar tool carrier having latching means carried at its lower end to connect onto the fishing head 43 of the tool carrier stuck within the well. As illustrated, the packer retaining elements or cups 36 and 37 surround the ends of the packer or sealing element 34 while at the same time being axially spaced from each other on the central body member 32 so that the packer element 34 is against, or may be expanded against, the inner Wall of a tubing string or pipe 21 to form a seal thereagainst. Preferably, the sealing elements 34 and 35 are formed having an internal diameter slightly larger than that of the body member 32-32:: so that undercut portions or annular spaces 44 are formed between the body members and the sealing elements.

Fluid ports 46 and 4'7 are provided through the wall of the packer retaining cups 37 and 38 near the closed ends thereof so that fluid passageways are formed through the packer retaining cups in communication between the spaces outside the packers and the annular spaces 44-. The packers or sealing elements 34 and 35 are made of any suitable inflatable and/or resilient material, such as rubber, synthetic rubber, rubberized fabrics, or certain plastic materials which may be expanded under the application of a pressure fluid. The portion of the sealing elements 34 and 35 in contact with the inner wall of a tubing string may have a thickened cross-section so as to provide for some wear on the seal as it is propelled through the tubing. In addition, the sealing elements 34 and 35 may be beveled to substantially a point, as illustrated, if desired.

The body member 32a is connected by means of a flexible joint 50 to a connector body member 51 which is adapted to latch onto a probe 52. The connector body member 51 is provided with two sets of latches, one latch 53 having a portion 54 adapted to engage a shoulder 55 on the probe 52. The other latch 56 is adapted to extend outwardly into a recess 57 formed within the inner wall of the pipe through which the tool is being circulated. The latches 53 and 56 are pivotally mounted on pins 53 and 59, respectively, which are positioned in the connector body member 51 parallel to the axis thereof. The operative latch 53 is bevelled, as at 60, so that the latch 53 will be rotated on its pin 58 to engage shoulder 55 of the probe 52 and locked thereon when the combined probe 52 in connector housing 51 are moved upwardly in the pipe 21. Both latches 53 and 56 may be springloaded.

In FIGURES 2A and 3 the latch 53 which normally engages the shoulder 55 of the probe 52 is shown as having dropped in the annular recess 57 so that the upper edge 54 of the latch 53 no longer engages the shoulder 55 of the probe 52 which is therefore free to be forced from the connector body member 51 by fluid pressure being applied through the bore 62 and 62a of the tool carrier, the bore 63 of the flexible joint 50, and the bore 64 through the connector body member 51. If desired, the connector body member 51 may be provided with packing element 65 for sealing against the probe 52 in a lluidtight manner. As the probe 52 is pushed by fluid pressure out of the connector body member 51, the other latch 56 is able to expand radially into the annular recess 57 since the camming end 66 of the latch 56 is at liberty to move into the bore 64 of the connector body member 51. Prior f0 this time, the presence of the probe 52 within the bore 64 of the connector body member 51 prevented the camming end 66 of the latch 56 from moving out of the position shown in FIGURE 3.

Thus, with the probe 52 out of the connector body member 51 and both latches 53 and 56 expanded into the annular recess 57, the tool carrier comprising body members 32 and 32a is fixedly locked in the pipe 21 and prevented from moving axially therein. Attached to the lower end of the probe 52 is another tool carrier or a pilot tool carrier of smaller diameter which is adapted to enter and pass down the portion of the pipe downstream of the constricted portion 26 of the pipe 21. The second tool carrier is equipped with one or more slidable packers or sealing elements 70 and 71 which may be identical with, and connected in a manner similar to, that described with regard to packers 34 and 35 of the larger diameter tool carrier. The packers 70 and 71 are flexibly connected together by a suitable flexible joint 72 with the lower packer 71 having a flexible joint 73 at its lower end by which it is connected to any suitable type of tool or instrument 74 which is to be placed down in the well.

In the operation of the two-diameter tool carrier of the present invention, fluid is pumped in back of the large diameter portion of the tool carrier to propel the large diameter tool carrier, together with the small diameter tool carrier in the tool secured thereto, through the flowline 21 until it reaches the constriction at point 26 (FIGURE 1). At this point the latch 53 (FIGURE 2A) drops out into the annular recess 57, releasing the probe 52 which permits fluid pressure to propel the small diameter tool carrier 70-71, the tool 74, and the probe 72 down the tubing string 21 and 24 of the well to a predetermined position to carry out a preselected operation. At any designated time the small diameter tool carrier 79-71 and its tool 74 are returned up the tubing string 24 and into the flowline 21 where the beveled upper end 75 (FIGURE 2) of the probe 52 contacts the camming end 66 of the latch 56, causing the latch 56 to be retracted to the position shown in FIGURE 5. Continued fluid pressure from below forces the tool carriers upwardly in FIGURES 2 and 2A as the upper beveled surface 60 of latch 53 causes the latch 53 to slide out of the annular recess 57 and be retracted into the body of the connector 51 while the shoulder 54 on latch 53 re-engages shoulder 55 on probe 52 to connect the two tool carriers together.

We claim as our invention:

1. Apparatus adapted to be pumped through a twodiameter pipe having portions of dissimilar internal diameters, said apparatus comprising a first body member, a. second body member, detachable and re-engageable connector means carried by one end of said first body member for connecting said second body member coaxial therewith, there being a flow passage through said first body member, first annular sealing means carried outwardly on said first body member and adapted to seal against a surrounding pipe, and second annular sealing means carried outwardly on said second body member, said second annular sealing means being of smaller external diameter than said first sealing means to seal within the small-diameter portion of said two-diameter pipe.

2. Apparatus adapted to be pumped through a twodiameter pipe having portions of dissimilar internal diameters, said apparatus comprising a first body member, a second body member, detachable and re-engageable connector means carried by one end of said first body member for connecting said second body member coaxial therewith, there being a flow passage through said first body member, first annular sealing means carried outwardly on said first body member and adapted to seal against a surrounding pipe, second annular sealing means carried outwardly on said second body member, said second annular sealing means being of smaller external diameter than said first sealing means to seal within the small-diameter portion of a two-diameter pipe, said connector means being actuatable by a change in diameter as it is pumped through said two diameter pipe.

3. Apparatus adapted to be pumped through a twodiameter pipe having portions of dissimilar internal diameters, said apparatus comprising a first body member, a second body member, detachable connector means carried by one end of said first body member for connecting said second body member coaxial therewith, there being a flow passage through said first body member, first annular sealing means carried outwardly on said first body member and adapted to seal against a surrounding pipe, second annular sealing means carried outwardly on said second body member, said second annular sealing means being of smaller external diameter than said first sealing means, said connector means being actuatable by a change in diameter as it is pumped through said two diameter pipe, and outwardly extendible latch means carried by said first body member for engaging the inner surface of said pipe on separation of said second body member from said first body member.

4. Apparatus adapted to be pumped through a twodiameter pipe having portions of disimilar internal di ameters, said apparatus comprising a first body member, a second body member, detachable connector means carried by one end of said first body member for connecting said second body member coaxial therewith, there being a flow passage through said first body member, first annular sealing means carried outwardly on said first body member and adapted to seal against a surrounding pipe, second annular sealing means carried outwardly on said second body member, said second annular sealing means being of smaller external diameter than said first sealing means, spring-loaded means carried by said connector means and being actuatable by a change in diameter as it is pumped through said two diameter pipe for disconnecting said connector means, outwardly extendible latch means carried by said first body member for engaging the inner surface of said pipe on separation of said second body member from said first body member, and shoulder means formed on said first body member for engaging a shoulder formed between portions of dissimilar internal diameters of said pipe against which said apparatus is adapted to be pumped.

5. The apparatus of claim 4 wherein said sealing means comprise at least a pair of selectively expandible annular sealing means carried on each body member in axially spaced relationship.

References Cited in the file of this patent UNITED STATES PATENTS 2,382,578 Penick Aug. 14, 1945 3,003,560 Corley et a1. Oct. 10, 1961 3,090,440 Lagucki May 21, 1963 

1. APPARATUS ADAPTED TO BE PUMPED THROUGH A TWODIAMETER PIPE HAVING PORTIONS OF DISSIMILAR INTERNAL DIAMETERS, SAID APPARATUS COMPRISING A FIRST BODY MEMBER, A SECOND BODY MEMBER, DETACHABLE AND RE-ENGAGEABLE CONNECTOR MEANS CARRIED BY ONE END OF SAID FIRST BODY MEMBER FOR CONNECTING SAID SECOND BODY MEMBER COAXIAL THEREWITH, THERE BEING A FLOW PASSAGE THROUGH SAID FIRST BODY MEMBER, FIRST ANNULAR SEALING MEANS CARRIED OUTWARDLY ON SAID FIRST BODY MEMBER AND ADAPTED TO SEAL AGAINST A SURROUNDING PIPE, AND SECOND ANNULAR SEALING MEANS CARRIED OUTWARDLY ON SAID SECOND BODY MEMBER, SAID SECOND ANNULAR SEALING MEANS BEING OF SMALLER EXTERNAL DIAMETER THAN SAID FIRST SEALING MEANS TO SEAL WITHIN THE SMALL-DIAMETER PORTION OF SAID TWO-DIAMETER PIPE. 